Near-Field light concentration by controlling polarization
Distribution of the near-field light is significantly affected by the aperture shape and surrounding material as well as its size. Using computer simulations, we explored the optimum aperture shape.
The pictures show computer simulations of near-field light distribution when the polarized light entered horizontally. The colors indicate the relative intensity of near-field light on an increasing scale from blue to red.
The upper picture shows the simulation of a triangular aperture. The near-field light is concentrated on one side of the triangle. The bottom picture is the simulation of a circular aperture. Intense near-field light is produced and dispersed to the left and right of the circumference. This shows that the triangular aperture is more desirable for high resolution.
Based on the simulations, the near-field light can be concentrated in an area much smaller than the actual aperture size by optimizing the shape of the aperture.
